Polarity indicating apparatus



Aug. 28, 1934. J. BUTTOLPH 1,971,399

I I POLARITY INDICATING APPARATUS Filed Aug. 1, 1930 n 5 WM Patented.Aug. 28, 1934 POLARITY INDICATING APPARATUS Leroy J. Buttolph,Grantwood, N. J., assignor to General Electric Vapor Lamp Company,

Hoboken, N. J a corporation of New Jersey Application August 1, 1930,Serial No. 472,473

8 Claims.

The present invention relates to electric apparatus, and particularly todirect current apparatus which is intended for use only with a givenpolarity. The invention consists in a new and novel combination ofapparatus, as hereinafter set forth and claimed.

A particular object of the invention is to providemeans to give anaudible signal whenever the leads to electrical apparatus, which is in-1 tended to operate with only one polarity, are

connected with incorrect polarity. Other objects and advantages of theinvention will appear from the following detailed specification or froman inspection of the appended drawing.

Many types of direct current apparatus are well known to be adapted foroperation .on only one polarity. While in some cases connection of suchapparatus to a source of reverse polarity results in no injury thereto,certain devices, such as mercury arc lamps, are subject to destructionif so operated. Some means of theproper polarity of the potentialapplied to such devices is therefore not only desirable, but frequentlyessential, especially where the devices are portable units which are tobe operated from outlets, such, for instance, as ultraviolet generatorsintended for home use. I have discovered that a signal device, such as apolarized buzzer, which is permanently associated with the apparatus maybe made to give an audible warning whenever the leads toiv the apparatushave a potential of reverse polarity applied thereto. Such a warning hasbeen found to be especially effective, since the insistent note of thebumer cannot fail to attract the attention at even a relatively carelessuser. Operation of the device with reverse polarity is therebyeifectively prevented,

For the purpose ofillustrating my invention I have shown two embodimentsthereof in the accompanying drawing, in which Fig. 1 is a diagrammaticrepresentation of a conventional quartz mercury vapor arc lamp circuit,with a polarized buzzer, shown in part section, connected across theleads to, said lamp, correct polarity being indicated as applied to saidleads,

Fig. 2 is a similar view of a portion oi! the circuit of Fig. 1, showingthe use of a diaphragm 5b to accentuate the noise from the Inner, the

application of reverse polarity to said leads being indicated, and

Fig. 3 is a ditic representation of an alternative embodiment ofapplicant's invention,

showingtheuseofanon-polaflzedbuzzerincombination with a rectifier inplace of the polarized buzzer of Figs. 1 and 2.

In the drawing, with particular reference to Fig. 1, there is shown atypical operating circuit for a standard quartz moi-"cury vapor arc lamp1 01' the direct current type. iamp has a mercury cathode 2 and atungsten anode 3, said cathode being connected through an inductance 4and lead 5 to one terminal of a conventional plug connector 6, while theanode 3 is connected through a resistance 7, switc and lead 9 to theother terminal of said connuior 6. Said connector 6 is adapted to beinserted in a conventional outlet 6' which is in turn connected to asuitable source of direct current.

As shown in Figs. 1 and 2 the polarized relay consists of a permanenthorseshoe magnet 10 having the bifurcated pole pieces 11 (north) and 12(south) extending toward each other. An annular magnet coil 13 ismounted in the openings in said polelpieces 11 and 12 with its axisnormal to the lines of force in the magnetic field between said polepieces. A soft iron armature 14 which extends through said coil 13 ispivoted in a suitable manner therein at a point which is equidistantfrom said pole pieces. A contact point 15 which is adapted to contactwith said armature 14 whenever said armature is in a normal position ofrest is connected to the lead 5, while a connection is likewise madefrom lead 9 tone end of the magnet coil 13 and from the other end of.said magnet coil to the armature 14. Where desired, a diaphragm 20 maybe connected to the lower end of the armature 14, as shown in Fig. 2.

In the circuit of Fig. 3, which is somewhat similar to that of Figs. 1and 2, the buzzer 16, which is non-polarized, has one terminal connectedto the lead 9, while the other terminal thereof is connected to theplate 18 of a conventional point to plate gas-filled rectifying tube1-7, the point electrode 19 of said tube in turn being connected to thelead 5.

In the mend operation of the novel combination of apparatus shown inFigs. 1 and 2, assumingthe plug connectorGtobeinserted lnthe outlet 6',and thus connected to a suitable source -01 direct'current with thepolarity as shown in Fig. 1, current flows from the lead 9 through themagnet coil 13, and thence through armature 14 and contact 15 tolead5.'1hearmature14,which is normally balanced between the pole pieces .11and IZ-asaresult-oftheequalforcesexezted thereon by eachoi' thesaidpolepiecsJs mag-.

netized by the current flowing through the n 13, the upper end beco: endnorth, with the result that the magnetic forces become unbalanced andthe armature tends to rotate in a counter-clockwise direction. Rotationin this direction is opposed, however, by the contact 15, so that thearmature 14 is maintained immobile, and makes no sound. The operator,being thereby notified that the polarity is correct, closes the switch 8and manipulates the mercury arc lamp 1 in the usual mannerto initiatethe discharge therethrough.

Assuming, however, that the plug connector 6 isreversed and thus has apotential applied thereto as indicated in current flows from lead 5through contact 15 and armature 14 to the magnet coil 13, which ittraverses in the reverse direction, and thence to load 9. The armatureis, of course, magnetized by the current flowing through the coil 13,the upper end becoming a north pole and the icwer end a south pole, theunbalanced magnetic forces thereupon causing rotation of said armaturein a clockwise direction; The circuit through said magnet coil 13 isthereupon broken at contact whereupon the armature 14 becomesdemagnetized and returns to its normal contact making position. Kinsobviously continues periodically, the armature vibrating between thepositions indicated by the dot and dash lines in Fig. 2, causing anoise, which is especially insistent when the diaphragm 20 is used, thatimmediately attracts attention and warns that polarity is li'iQ-Ql'lzitioperator thereupon reverses the plug connector 6, whereupon the armature14 is silenced and the operator proceeds to close the switch 8 and tostart the arc in the usual manner.

In the circuit of Fig. 3, assuming the plug conmotor 6 to be connectedto a suitable source of direct current or the indicated polarity. theplate electrode 18 of the conventional point to plate gas-filledrectifying tube 17 is positive, while the point electrode 19 thereof isnegative, so that no appreciable current can pass therebetween, due tothe small area of the negative electrode. As a result the buzzer 16 isinoperative, and the operator proceeds as in Fig. 1 to close the switch8 and to start the are. If the potential applied to the plug connector 6be reversed, however, the plate electrode 18 is negative and serves as acathode, passing an appreciable current which flows from the lead 5 tothe point electrode 19. thence through the gaseous atmosphere within thetube 1'7 to the plate electrode 18, and then through the buzzer 16 backto the lead 9. The

buzzer armature is thereby caused to vibrate,

producing the desired warning note- The operator thereupon reverses theplug connector 6 and proceeds in the usual manner to start the arc.

While I have indicated the use of a switch 8 in each of the embodimentsor my'invention, it is obvious that where the buzzer is designed toprotect a device such as the mercury arc lamp 1, in

which the circuit is incomplete until the lamp has been manually tippedto cause the mercury to bridge the electrodes thereof, this switch maybe omitted; or it may, if desired, be located be-- is subject todestruction it operated with reverse tween the plug 8 and the point ofconnection of thebuzzer circuit, in order to permit the device to besemi-permanently plugged into a suitable outlet without -causing thebuzzer to continuously absorb energy while the lamp or the like is notin operation.

While I have illustrated my invention by reference to specificembodiments thereof, it is to be understood that various changes.omissions or south and the lower mally open,

substitutions, within the cope of the appended claims, may be madetherein without departing from the spirit thereoi.

I.claim as my invention:

1. In combination, a direct current device which is subject todestruction it operated with reverse polarity, leads to said device, andmeans connected to said leads in shunt to said device for giving anaudible signal when a predetermined polarity is applied to said leads,the circuit through said device being normally open.

2. In combination, a direct current device which is subject todestruction it operated with reverse polarity, leads to said .device,and means con nected to said leads in shunt to said device for giving anaudible signal when the polarity applied to said leads is the reverse ofthat required by said'device, the circuit through said device beingnormally open.

3. In combination, a direct currentdevice which is subject todestruction it operated with reverse polarity, leads to said device,means connected to said leads in shunt to said device for giving anaudible signal when a predetermined polarity is connected to saiddevice, and a switch in said leads between said device and said signal.

- 4. In combination, a direct current electric gaseous discharge devicewhich is subject to destruction if operated with reverse polarity, leadstosaid device,-and an audible signal, said signal having an operatingcoil connected to said leads in shunt to said device and a polarizearmature which intermittently opens the circuit through .said coil whena predetermined polarity is applied to said leads, the circuit throughsaid device being normally open.

5. In combination, a direct current mercury vapor arc device which issubject to destruction if operated with reverse polarity, leads to saiddevice, an audible signal, said signal having an op- 11.: crating coilconnected to said leads in shunt to said device and a polarized armaturewhich intermittently opens the circuit through said coil when apredetermined polarity is applied to said leads, and a switch betweensaid coil and said device.

6; In combination, a direct current mercury vapor arc device which issubject to destruction it operated with reverse polarity, leads to saiddevice, an audible signal having an operating coil connected to saidleads in shunt to said device and means operated by said coil tointermittently open the circuit through said coil when the polarityapplied to said leads is the reverse or that required by said device,the circuit through said device being normaily open.

7. In combination, a direct current mercury vapor arc device which issubject to destruction ll. operated with reverse polarity, leads to saiddevice, an audible signal having an operating coil connected to saidleads in shunt to said device, means operated by said coil tointermittently open the circuit through said coil when the polarityapplied to said leads is the reverse of that required by said device anda switch between said coil and said device.

8. In combination, a direct current device which LEROY .1. BU'I'IQLPH.

